APPARATUS AND METHOD FOR DETERMINING ANGULAR POSITION

摘要

The position of a rotor of a motor is determined. The motor includes the rotor and a stator and the stator includes a plurality of coils. The rotor further includes at least one rotating magnetic field device. When the rotor is moving below a threshold speed, the current in each of the plurality of coils of the stator is measured. A pre-programmed data structure is accessed. The pre-programmed data structure stores a plurality of stator currents associated with a plurality of predetermined rotor positions. A first absolute position of the rotor is determined from the data structure according to the measured current from each of the plurality of coils. When the rotor is moving above the threshold speed, one or more rising or falling edges of magnetic field strength associated with the at least one rotating magnetic field device of the rotor are sensed. At least one timing aspect of the rising and falling edges of magnetic field strength are compared to determine a second absolute position of the rotor.